摘要：针对机械波合成的非正弦谐振式压电马达对振子精度要求高的问题，以合成谐振方波的振子为例阐述了如何在振子加工精度不高时，调整其前两级共振频率并使其满足合成近似方波的要求。首先设计了满足近似方波合成的振子，然后用有限元法研究了3个调整方法：① 改变振子夹持位置；② 改变振子夹持位置与压电陶瓷尺寸；③ 改变振子夹持位置与压电陶瓷的粘贴位置。方法1操作简单、省时，频率变化规律性不明显；方法2操作复杂，需反复粘贴压电片，费时费力，频率变化规律很明显，易调整；方法3对频率比没有太大影响，但是可以改变基频大小，也有参考价值。最后进行实验，实验结果与仿真结论相符，且波形为近似方波。
关键词：压电马达；共振；机械波合成；方波

Abstract: Aiming at solving the problem of high accuracy requirementof the vibrator for PZT motor which is driven by synthesized mechanical nonsinusoidalresonance wave, taking the vibrator of synthetic resonant wave as an example, expounded how to adjust the first two levels of resonance frequency to meet the requirement of the synthesizing approximate square wavewhen the machining accuracy of the vibrator is not high.Firstly, a piezoelectric cantilever beam satisfying the approximate square wave synthesis was designed, and then three adjustment methods were studied by using the finite element method: ① just changed the clamping position of the vibrator; ② changed the clamping position of vibrator and the size of piezoelectric ceramic; ③ changed the clamping position of the vibrator and the piezoelectric ceramic paste position. The first method is simple and timesaving, but the regularity of frequency changing is not obvious, so it is difficult to control; the second method is more complicated and the PZT sheet needed to be pasted repeatedly which is timeconsuming and laborious, but the frequency regularity of frequency changing is very obvious, it is easy to adjust; the third method basically do not have much influence on the frequency ratio, but the fundamental frequency can be changed by this method which still has reference value.Finally, the experiment was carried out, and the experimental results are consistent with the simulation results, and the shape of the wave is approximate squarewave.
Key words: piezoelectric ceramics; cantilever; resonant; waveform synthesis; square wave